Add metering and event ttl config options

ceilometer.conf template >= Kilo does not contain metering-time-to-live
and event-time-to-live parameters. Add these options so we can control
ceilometer database growth.

Change-Id: Id5831280daeb582586bfa615268309c4abec5d63
Closes-Bug: 1561220

config.yaml

@@ -7,6 +7,16 @@ options:
     default: False
     type: boolean
     description: Enable verbose logging.
+  metering-time-to-live:
+    type: int
+    default: -1
+    description: |
+      Number of seconds that samples are kept in the database for (<= 0 means forever)
+  event-time-to-live:
+    type: int
+    default: -1
+    description: |
+      Number of seconds that events are kept in the database for (<= 0 means forever)
   use-syslog:
     type: boolean
     default: False

lib/ceilometer_contexts.py

@@ -92,9 +92,11 @@ class CeilometerContext(OSContextGenerator):
         from ceilometer_utils import get_shared_secret
 
         ctxt = {
-            'api_workers': config('api-workers'),
             'port': CEILOMETER_PORT,
-            'metering_secret': get_shared_secret()
+            'metering_secret': get_shared_secret(),
+            'api_workers': config('api-workers'),
+            'metering_time_to_live': config('metering-time-to-live'),
+            'event_time_to_live': config('event-time-to-live'),
         }
         return ctxt
 

templates/kilo/ceilometer.conf

@@ -28,6 +28,8 @@ mongodb_replica_set = {{ db_replset }}
 {% else -%}
 connection = mongodb://{{ db_host }}:{{ db_port }}/{{ db_name }}
 {% endif %}
+metering_time_to_live = {{ metering_time_to_live }}
+event_time_to_live = {{ event_time_to_live }}
 
 [publisher_rpc]
 metering_secret = {{ metering_secret }}

templates/mitaka/ceilometer.conf

@@ -26,6 +26,8 @@ mongodb_replica_set = {{ db_replset }}
 {% else -%}
 connection = mongodb://{{ db_host }}:{{ db_port }}/{{ db_name }}
 {% endif %}
+metering_time_to_live = {{ metering_time_to_live }}
+event_time_to_live = {{ event_time_to_live }}
 
 [publisher]
 telemetry_secret = {{ metering_secret }}

unit_tests/test_ceilometer_contexts.py

@@ -129,6 +129,8 @@ class CeilometerContextsTest(CharmTestCase):
             'port': 8777,
             'metering_secret': 'mysecret',
             'api_workers': 1,
+            'metering_time_to_live': -1,
+            'event_time_to_live': -1,
         })
 
     def test_ceilometer_service_context(self):